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784.
Based on quantum chemistry calculations combined with the Marcus–Hush electron transfer theory, we investigated the charge‐transport properties of oligothiophenes (nTs) and oligopyrroles (nPs) (n=6, 7, 8) as potential p‐ or n‐type organic semiconductor materials. The results of our calculations indicate that 1) the nPs show intrinsic hole mobilities as high as or even higher than those of nTs, and 2) the vertical ionization potentials (VIPs) of the nPs are about 0.6–0.7 eV smaller than the corresponding VIPs of the nTs. Based on their charge‐transport ability and hole‐injection efficiency, the nPs have potential as p‐type organic semiconducting materials. Furthermore, it was also found that the maximum values of the electron‐transfer mobility for the nTs are larger by one‐to‐two orders of magnitude than the corresponding maximum values of hole‐transfer mobility, which suggests that the nTs have the potential to be developed as promising n‐type organic semiconducting materials owing to their electron mobility. 相似文献
785.
Hierarchical flower-like architectures of[Ni3(BTC)2·12H2O](BTC3=benzene-1,3,5-tricarboxylate) were successfully prepared by a simple solution-phase method under mild conditions without any template or surfactant.Phase-pure porous NiO nanocrystals were obtained by annealing the Ni-BTC complex without significant alteration in morphology.The product was characterized by X-ray diffraction techniques,field-emission scanning electron microscopy(FESEM).transmission electron microscopy(TEM) and high-resolution TEM(HRTEM).The catalytic effect of the NiO product was investigated on the thermal decomposition of ammonium perchlorate(AP) and it was found that the annealed NiO product has higher catalytic activity than the commercial NiO. 相似文献
786.
In this paper,we developed and validated a simple,sensitive,and selective high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) method to identify and measure the following prohibited substances that may be found in cosmetic products:minoxidil,hydrocortisone, spironolactone,estrone,canrenone,triamcinolone acetonide and progesterone.Chromatographic separation was performed on a Waters Symmetry C18(100 mm×2.1 mm,3.5μm particle size) with a gradient elution system composed of 0.2%(v/v) formic acid aqueous solution and methanol containing 0.2%(v/v) formic acid at a flow rate of 0.3 mL/min.The substances were detected using a triple quadrupole mass spectrometer in the multiple reaction monitoring mode with an electrospray ionization source.All of the calibration curves showed good linearity(r > 0.999) within the tested concentration ranges.The limit of detection was <25 pg.The relative standard deviations for intraday precision for each of the prohibited substances were <3.5%at two concentration levels(2μg/g,10μg/g). The relative recovery rate for each of the prohibited substances ranged from 91.8%to 111%at three concentration levels(0.1μg/g,2μg/g,10μg/g),including the limit of quantification.In conclusion,we have developed and validated a method that can identify seven prohibited substances in cosmetic products. 相似文献
787.
Jun Yuan Ye Zhong Shiliang Li Xue Zhao Guoqin Luan Zhenjiang Zhao Jin Huang Honglin Li Yufang Xu 《中国化学》2013,(9):1192-1198
A series of triazole and benzotriazole derivatives as novel p90 ribosomal S6 protein kinase 2 (RSK2) inhibitors were designed and synthesized. The in vitro activities against RSK2 were evaluated, and among 14 compounds, compounds 5, 6, 11, 12, 13 and 14 exhibited enzyme IC50 values of 8.91, 2.86, 3.19, 3.05, 4.49 and 2.09 μmol/L re- spectively. The proposed binding modes were simulated using molecular docking method, and the docking results coupled with the stmcture-activi1:y relationship (SAR) analysis indicated that all these active compounds bound to the RSK2 ATP binding site at NTKD, and the electron-donating groups on the 4-position of phenyl were the deter- minant point for the inhibitory activity. 相似文献
788.
配体[C5Me4HR][R=4-BrPh(1),(MeC5H3N)CH2(2)]分别与Mo(CO)6,Ru3(CO)12和Fe(CO)5在二甲苯中加热回流,得到了6个双核配合物trans-[η5-C5Me4R]2Mo2(CO)6(3,4),trans-[(η5-C5Me4R)Ru(CO)(μ-CO)]2(5,6)和trans-[η5-(C5Me4R)Fe(CO)(μ-CO)]2(7,8,).通过元素分析、红外光谱、核磁共振氢谱对配合物的结构进行了表征,并用X-射线单晶衍射法测定了配合物3,5,6和8的结构. 相似文献
789.
790.
The electrochemical behavior of dopamine (DA) at a MWNTs-modified glassy carbon electrode was investigated by cyclic voltammetry (CV), square wave voltammetry (SWV). The MWNTs modified electrode exhibited marked promotion of the electrochemical reaction of DA in different environments. Under optimum conditions, the peak currents of SWV of DA were increased linearly with incremental concentration of DA in the range from 5 × 10?7 to 1 × 10?5 mol L?1. The limit of detection is 3 × 10?7 mol L?1. 相似文献